A Recessive Gene
by SteveTheNarwhal
Summary: It's a basic law of genetics- every new trait must originate somewhere. How the Blacks became brave.


Regulus knew what he had to do. The only issue now was getting up the courage to go through with it. And he had never been known for his courage.

Trying to postpone his decision for as long as possible, he shambled into the parlor, which was as spotless as everything else in the Black residence. Well, except for Sirius's room. He was pretty sure no one had been in there since the night his mother had attempted to rip down all the decorations, only giving up when she had encountered a nasty hex on one of the Gryffindor banners. Despite his present situation, Regulus had to suppress a grin. He hadn't even known it was possible for his mother to look uglier, but the tentacles had certainly done their best.

Remembering what else had happened that night, Regulus's smirk faded. He crossed to the opposite side of the room, and looked at the tiny burn that used to be his brother. He usually tried not to look at it, but tonight, it drew his eye.

He ran his hand over the tapestry, feeling the centuries-old cloth brush against his skin. He reached to touch Sirius's burn, but stopped himself at the last moment. Instead he reached up to touch the first mark— the one that had started him down this path in the first place. Because Regulus knew the truth.

It was whispered in the pureblood circles that the Blacks had a tendency towards madness. Cropping up every generation, it was viewed as an unfortunate side effect to the preservation of the bloodline. His mother was the mad one of her generation, and people said that his cousin Bellatrix was the latest to succumb to the disease. But Regulus knew— they were all mad. There were the quietly dark ones, like him and his cousin Andromeda. There were the reckless, fierce ones, like Sirius and Bellatrix. And there were the vapid, egotistical ones, like his father and his cousin Narcissa. All proud and beautiful and _insane_.

No, madness was not the recessive weakness of the Blacks. It was goodness. Every generation, there would be a Black who couldn't handle their legacy. Another _hero_ looking for a noble cause to die for. Another girl with a taste for forbidden love. Another person unable to live with the family's expectations. Another burn in ancient fabric.

And it had all started with _her._ Regulus knew her name, even though it had been eradicated long ago.

_Isla_.

Isla turned to see herself in her golden mirror, which had been a gift from her eldest brother Phineas for her betrothal. The aforementioned engagement was to be announced tonight, after the Black Christmas ball. The one that she would _not_ be attending.

_Perfect_, she thought to herself. In her Muggle dress, she felt like a completely different person. Someone beautiful, appreciated, and loved. Not just Elladora's plain little sister, the almost-Squib with the enormous dowry. Just Mrs. Hitchens, the tailor's wife. _Mrs. Hitchens_. Her stomach fluttered even thinking about it. And it would all become reality after tonight.

There was just one last thing to take care of…

Quickly, as if making the separation faster would make it easier, she took out her wand and laid it on the bed. She couldn't take it with her. Bob didn't know about magic, and she planned to keep it that way. He was extremely practical, and she wasn't sure how much more she could disrupt his world before he pulled away. Understanding that she was of high birth had been enough of a stretch for him. He had known her only as the girl who was constantly running in to have her dresses mended. She couldn't help it that she was clumsy and couldn't cast a _Reparo _to save her life.

With her mind happily running over the rest of their whirlwind romance, she was able to walk away from her wand with little struggle. Only when she reached her door did she hesitate.

True, she was no good at magic. But did she really want to give it up for the rest of her life? What if she needed it one day? Her Black self-preservation engulfed her in one last desperate attempt to change her mind. She couldn't leave. She _couldn't_. It just wasn't done. She was a _Black_.

But she was the mutation. The freak. And a spark of courage had formed inside of her, the same spark that would finish the Black line for good.

Isla opened the door to her bedroom, and walked out.

Regulus opened the door to the parlor, and walked out.


End file.
